水电能源科学

某抽水蓄能电站下水库所处岩溶环境复杂，为此建立三维渗流分析有限元模型，对库区主要建筑物和岩溶通道进行模拟，采用“坝基防渗帷幕深度为0.5倍坝前水头、两岸防渗帷幕深度为3 Lu线以下3 m、右岸防渗帷幕长度为200 m、设置单排帷幕”作为初步渗控方案，对库区渗流场、渗透坡降及渗透量进行计算分析，发现初步渗控方案满足规范要求，但渗流量和渗透坡降接近临界值。为优化渗控方案，基于初步渗控方案，改变两岸帷幕深度、坝基帷幕深度、右岸帷幕长度、设置双排帷幕4项指标，研究各指标变化对库区渗透量的影响，提出优化渗控方案。分析结果表明，初步方案基础上，在坝基处布置双排帷幕，坝基渗透流量减少267.3 m³/d,库区渗控效果显著。

Aiming at the complex karst environment of the lower reservoir of a pumped storage power station, a three-dimensional finite element model for seepage analysis was established to simulate the main buildings and karst passageways in the reservoir area. "The depth of seepage control curtain at the base of the dam is 0.5 times of the pre-dam head, the depth of seepage control curtain on both sides of the dam is 3 m below the 3 Lu line, the length of seepage control curtain on the right side of the dam is 200 m, and a single-row curtain is set up" is used as the preliminary seepage control scheme. The seepage field, infiltration slope and infiltration volume of the reservoir area were calculated. The preliminary seepage control scheme met the specification requirements. But the seepage rate and infiltration slope were close to the critical value. The four indexes of curtain depth on both sides of the bank, curtain depth at the base of the dam, length of curtain on the right bank, and double-row curtain were changed to optimize seepage control scheme. The impact of the changes of the indexes on the infiltration volume of the reservoir area was investigated so that the optimization of the seepage control scheme was put forward. The analysis results show that on the basis of the preliminary scheme, the double-row curtain is set up at the dam base, the infiltration flow at the dam base is reduced by 267.3 m³/d, and the effect of seepage control in the reservoir area is remarkable.